1. Field of the Invention
Exemplary embodiments of the present invention relate to a switching apparatus and method of an RF module and a multi-input multi-output (MIMO) transceiver in a wireless communication system; and, more particularly, to a switching apparatus and method of an RF channel module according to change in the number of antennas used in each channel of a wireless communication system using multi-channels, and a switching apparatus and method of a MIMO transceiver therein.
2. Description of Related Art
In general, a wireless communication system uses a single continuous band. As a representative method for increasing the throughput of a wireless communication system, there are a method which increases a bandwidth and a MIMO method which increases the number of antennas and transmits and receives signals therethrough. However, when it is difficult to continuously increase a bandwidth, there is a need for a method which discontinuously increases a bandwidth by simultaneously using a single bandwidth and another bandwidth spaced apart therefrom.
The bandwidth can be continuously increased by fixing the number of RF communication modules and increasing only a channel bandwidth supported in each RF communication module. On the other hand, the bandwidth can be discontinuously increased by separately implementing RF communication modules for each bandwidth because a plurality of bandwidths may be spaced relatively far apart.
In order to support the MIMO scheme to the discontinuous multi-channels, a plurality of RF communication modules are implemented in each multi-channel. For example, a total of sixteen RF communication modules are implemented in order to support two multi-channels and support eight antennas to each channel. However, the RF communication module occupies a significant portion (¼ to ⅓) of a board area, which increases a manufacturing cost and causes a serious system power supply problem. To solve these problems, there is a need for an RF channel module (including an antenna, an RF processing module, a clock, an analog/digital (A/D) converter, and a digital/analog (D/A) converter) which has a smaller size and higher convergence in order to reduce a board area of a single RF chain.
However, the size of the existing RF channel module is high in the completion degree of development and there is beyond the improvement thereof. Also, even though the board area of the single RF channel is reduced by the system convergence, the reduced margin width is insufficient in relation to the expansion of the spatial size caused by several times increase in the number of the RF channels.
Also, the complexity of the MIMO transceiver has high dependency on the number of streams supported in the wireless communication system. In order to simultaneously transceiver a lot of streams, a more complex MIMO transceiver is required. As in the above example, in order to support two multi-channels and support eight antennas to each channel, two MIMO transceiver processors supporting eight-antenna processing are required.
Also, there is a technique which shares RF channel modules when a single terminal supports a plurality of protocols. For example, when a single terminal supports three communication protocols, such as a Bluetooth protocol, a wireless LAN protocol, and a cellular protocol, an integrated switching module is constructed such that RF channel modules are shared through switching, a baseband is implemented according to each protocol, and a communication is performed without overlapping of the independent protocols. Such a method can support a MIMO scheme by switching the RF channel modules according to situations because it is most likely for a single terminal to use a single communication protocol and it is least likely for a single terminal to simultaneously use a plurality of communication protocols.
However, since the characteristics of the RF channel modules may be changed between heterogeneous devices, the RF channel module must be designed to support a plurality of physical characteristics. Also, in order to simultaneously support independently operating protocols, it may be very difficult to logically design an integrated switching module. Furthermore, such a method must share only the RF channel modules by switching, and baseband hardware must be independently used.